A COASTAL GEO-ECONOMIC MODEL FOR ARTIFICIAL DUNE MANAGEMENT IN NEW JERSEY

Following the devastating effects of Superstorm Sandy in October 2012, the State of New Jersey adopted and installed large-scale berm-dune structures with the goal of enhancing coastal resilience to future storms. Specifically, artificial dunes have been constructed by the US Army Corps of Engineers in accordance with the FEMA “540-Rule” design. The management goal of dune construction was to mitigate storm-related damages, thereby ensuring continuation and growth of beachfront tourism. Because some communities tend to value aesthetics (i.e. beachfront viewership) over protection or may begin to lower their perceptions of storm damage risks over time, it is unclear whether beachfront communities are willing to afford the costs of maintaining these projects in the future. To tackle this question, we develop a “geo-economic” model that captures the natural processes of beach and dune erosion and migration via storm overwash coupled with engineering interventions of beach nourishment and dune construction. The economic portion of the model accounts for the relationship between property values and berm-dune geometry. By deriving mathematical expressions for optimal berm and dune size as a function of geologic and economic parameters, our model suggests that conflicting preferences for coastal protection versus aesthetics could affect the willingness of property owners to maintain large-scale berm-dune structures in the long-term.